Chapter 25, Problem 1TYK

Summary Introduction

Introduction:

The history of earth mainly concerns with the development of the planet earth from the day it was formed to the present day. All branches of natural science have participated in the understanding of the main events, which took place in the earth’s past and are characterized by constant geological alteration and biological evolution.

Answer to Problem 1TYK

Correct answer:

Earth was formed $4.6\times {10}^9$ years ago whereas the oldest known living cell formed about $\text{3}{\text{.5×10}}^{\text{9}}$ years ago.

Explanation of Solution

Justification/explanation for the correct answer:

Option (d) is $4.6\times {10}^9$. Big Bang Theory, which was discovered by an astronomer George Lemaitre, states about the great explosion that occurred 14 billion years ago and the Permian period, which tells about the largest extinction of animals that took place 250 million years ago so, they give the proof of the existence of the earth and the living cell. Earth was formed $4.6\times {10}^9$ years ago whereas the oldest known living cell formed about $\text{3}{\text{.5×10}}^{\text{9}}$ years ago. Hence, option (d) is correct.

Explanation for the incorrect answers:

Option (a) is that Earth was formed about ${\text{400×10}}^{\text{3}}$ years ago whereas the oldest known living cell was formed about $\text{3}{\text{.6×10}}^6$ years ago. It is not correct as it is not possible that the cell was found $\text{3}{\text{.6×10}}^6$ years ago and earth comes into existence ${\text{400×10}}^{\text{3}}$ years ago. So, it is an incorrect option.

Option (b) is that Earth was formed $4.6\times {10}^9$ years ago whereas the oldest known living cell formed about $\text{1}{\text{.0×10}}^{\text{9}}$ years ago. It is partially correct as the earth was formed $4.6\times {10}^9$ years ago but the cell was not formed $\text{1}{\text{.0×10}}^{\text{9}}$. So, it is an incorrect option.

Option (c) is that earth was formed $3.8\times {10}^9$ years ago whereas the oldest known living cell formed about $\text{4}{\text{.6×10}}^7$ years ago. It is not correct as the largest extinction of animals took place around 250 million years ago that is $\text{2}{\text{.5×10}}^8$. So, it is not possible that the cell was found $\text{4}{\text{.6×10}}^7$ years ago and earth came into existence $3.8\times {10}^9$ years ago. So, it is an incorrect option.

Option (e) is that earth was formed about $2.0\times {10}^9$ years ago whereas the oldest known living cell formed about ${\text{600×10}}^6$ years ago. It is not correct as the largest extinction of animals took place 250 million years ago, that is, $\text{2}{\text{.5×10}}^8$. So, it is not possible that the cell was found ${\text{600×10}}^6$ years ago and earth came into existence $2.0\times {10}^9$ years ago. So, it is an incorrect option.

Hence, options, (a), (b), (c), and (e) are incorrect.

Conclusion

Thus, it can be concluded that because Big Bang theory and Permian period gave the proof for the existence of earth and living cell.